noises when sleepy?

I'm not sure how long this has been going on because I don't normally see Rambo asleep but we brought her in on Sunday and in the last two or three days I've noticed what I think could be some sort of respiratory problem.
Most of the time she breathes silently but when she's asleep or bordering on sleep she sometimes makes a wheezing/snoring type noise. It's not constant but tends to be every breath for a few minutes then stops for a while.
I wasn't that worried but tonight she's made a noise twice that only lasts a second or two but sounds like someone hacking up phloem or a cat with a hairball. Both times she made the noise after the snoring type noises and then they've gone away. She sneezed once earlier as well.

Her nose and eyes look totally fine, no discharge of any kind, and she wasn't making the noises when we clipped her nails yesterday even though she was stressed and breathing heavily.

Does anyone have any idea what it could be? I prefer to do some reading before I go to the vet so I'm more aware of what we should be doing/what treatments should be offered etc.
Also, is it something that I should take her to the vet for tonight or could it wait for tomorrow?

Thanks :wave:

I have buns that snore. I find it cute to listen to them when I am working from home.

If you are worried, I would ask the vet to listen to her chest. I've not got any further advice to offer, I'm afraid, but I hope she's OK.